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Miao Y, Sun X, Gao G, Jia X, Wu H, Chen Y, Huang L. Evaluation of (-)-epigallocatechin-3-gallate (EGCG)-induced cytotoxicity on astrocytes: A potential mechanism of calcium overloading-induced mitochondrial dysfunction. Toxicol In Vitro 2019; 61:104592. [DOI: 10.1016/j.tiv.2019.104592] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/03/2019] [Accepted: 07/03/2019] [Indexed: 01/09/2023]
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2
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Choi WY, Kang DH, Lee HY. Enhancement of Neuroprotective Effects of Spirulina maxima by a Low-temperature Extraction Process with Ultrasonic Pretreatment. BIOTECHNOL BIOPROC E 2018. [DOI: 10.1007/s12257-018-0066-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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3
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Weng M, Xie X, Liu C, Lim KL, Zhang CW, Li L. The Sources of Reactive Oxygen Species and Its Possible Role in the Pathogenesis of Parkinson's Disease. PARKINSON'S DISEASE 2018; 2018:9163040. [PMID: 30245802 PMCID: PMC6139203 DOI: 10.1155/2018/9163040] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/29/2018] [Accepted: 07/24/2018] [Indexed: 02/07/2023]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra. The precise mechanism underlying pathogenesis of PD is not fully understood, but it has been widely accepted that excessive reactive oxygen species (ROS) are the key mediator of PD pathogenesis. The causative factors of PD such as gene mutation, neuroinflammation, and iron accumulation all could induce ROS generation, and the later would mediate the dopaminergic neuron death by causing oxidation protein, lipids, and other macromolecules in the cells. Obviously, it is of mechanistic and therapeutic significance to understand where ROS are derived and how ROS induce dopaminergic neuron damage. In the present review, we try to summarize and discuss the main source of ROS in PD and the key pathways through which ROS mediate DA neuron death.
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Affiliation(s)
- Minrui Weng
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Xiaoji Xie
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Chao Liu
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593
| | - Kah-Leong Lim
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593
| | - Cheng-wu Zhang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Lin Li
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
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4
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Enhancement of Neuroprotective Effects of Spirulina platensis Extract from a High-Pressure Homogenization Process. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8040634] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Esmaeelpanah E, Razavi BM, Vahdati Hasani F, Hosseinzadeh H. Evaluation of epigallocatechin gallate and epicatechin gallate effects on acrylamide-induced neurotoxicity in rats and cytotoxicity in PC 12 cells. Drug Chem Toxicol 2017; 41:441-448. [DOI: 10.1080/01480545.2017.1381108] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Elahe Esmaeelpanah
- School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Bibi Marjan Razavi
- Targeted Drug Delivery Research Center, Department of Pharmacodynamy and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Hossein Hosseinzadeh
- Pharmaceutical Research Center, Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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Glutathione-Dependent Detoxification Processes in Astrocytes. Neurochem Res 2014; 40:2570-82. [PMID: 25428182 DOI: 10.1007/s11064-014-1481-1] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 11/10/2014] [Accepted: 11/15/2014] [Indexed: 01/17/2023]
Abstract
Astrocytes have a pivotal role in brain as partners of neurons in homeostatic and metabolic processes. Astrocytes also protect other types of brain cells against the toxicity of reactive oxygen species and are considered as first line of defence against the toxic potential of xenobiotics. A key component in many of the astrocytic detoxification processes is the tripeptide glutathione (GSH) which serves as electron donor in the GSH peroxidase-catalyzed reduction of peroxides. In addition, GSH is substrate in the detoxification of xenobiotics and endogenous compounds by GSH-S-transferases which generate GSH conjugates that are efficiently exported from the cells by multidrug resistance proteins. Moreover, GSH reacts with the reactive endogenous carbonyls methylglyoxal and formaldehyde to intermediates which are substrates of detoxifying enzymes. In this article we will review the current knowledge on the GSH metabolism of astrocytes with a special emphasis on GSH-dependent detoxification processes.
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Mapping NAD(+) metabolism in the brain of ageing Wistar rats: potential targets for influencing brain senescence. Biogerontology 2013; 15:177-98. [PMID: 24337988 DOI: 10.1007/s10522-013-9489-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 12/09/2013] [Indexed: 12/21/2022]
Abstract
Over the last decade, the importance of NAD(+) has expanded beyond its role as an essential cofactor for energy metabolism. NAD(+) has emerged as a major signalling molecule that serves as the sole substrate for several enzymatic reactions including the DNA repair enzyme, poly(ADP-ribose) polymerase (PARP), NAD-dependent protein deacetylases or CD38, and transcriptional factors by a new class of histone deacetylases known as sirtuins. NAD(+) levels are regulated by the metabolic status and cellular stress caused by oxidative stress and DNA damage. Since a detailed study of NAD(+) metabolism in the healthy ageing mammalian brain is nascent, we examined the effect of ageing on intracellular NAD(+) metabolism in different brain regions in female Wistar rats in young (3 months), middle aged (12 months) and older adults (24 months). Our results are the first to show a significant decline in intracellular NAD(+) levels and NAD:NADH ratio with ageing in the CNS, occurring in parallel to an increase in lipid peroxidation and protein oxidation (o- and m-tyrosine) and a decline in total antioxidant capacity. Hyperphosphorylation of H2AX levels was also observed together with increased PARP-1 and PARP-2 expression, and CD38 activity, concomitantly with reduced NAD(+) and ATP levels and SIRT1 function in the cortex, brainstem, hippocampus and cerebellum. Reduced activity of mitochondrial complex I-IV and impaired maximum mitochondrial respiration rate were also observed in the ageing rat brain. Among the multiple physiological pathways associated with NAD(+) catabolism, our discovery of CD38 as the major regulator of cellular NAD(+) levels in rat neurons indicates that CD38 is a promising therapeutic target for the treatment of age-related neurodegenerative diseases.
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8
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Chemopreventive potential of the tannase-mediated biotransformation of green tea. Food Chem 2012; 133:358-65. [DOI: 10.1016/j.foodchem.2012.01.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 11/23/2011] [Accepted: 01/16/2012] [Indexed: 12/17/2022]
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Abarikwu SO, Pant AB, Farombi EO. 4-Hydroxynonenal induces mitochondrial-mediated apoptosis and oxidative stress in SH-SY5Y human neuronal cells. Basic Clin Pharmacol Toxicol 2011; 110:441-8. [PMID: 22118713 DOI: 10.1111/j.1742-7843.2011.00834.x] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Excessive and sustained increases in oxidative stress and apoptosis have been implicated in the pathogenesis of many diseases. In this study, we demonstrated that 4-hydroxynonenal (4-HNE), a product of lipid peroxidation in a range of concentration (0.1-50 μM) showed cytotoxic effects on SH-SY5Y cell culture at a concentration >5 μM at 4 hr of exposure. 4-HNE dose dependently decreased cell viability and significantly promoted reactive oxygen species formation and enhanced oxidative stress as reflected in the increased level of lipid peroxidation and catalase activity and decreased glutathione peroxidase activity as well as glutathione levels. 4-HNE-induced oxidative stress was associated with increased transcriptional and translational expressions of Bax and p53 in SH-SY5Y cells. Mitochondrial-mediated apoptosis was confirmed by increased expression and activity of caspase-3. Our data demonstrate that 4-HNE induces neuronal cell death through abnormal expression of apoptotic markers (p53, Bax and caspase-3). Oxidative stress may be involved in the initial priming of SH-SY5Y cells to 4-HNE-induced cytotoxicity in vitro.
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Affiliation(s)
- Sunny O Abarikwu
- Department of Chemical Sciences, College of Natural Sciences, Redeemer's University, Redemption City, Ogun State, Nigeria.
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Α-mangostin, a polyphenolic xanthone derivative from mangosteen, attenuates β-amyloid oligomers-induced neurotoxicity by inhibiting amyloid aggregation. Neuropharmacology 2011; 62:871-81. [PMID: 21958557 DOI: 10.1016/j.neuropharm.2011.09.016] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 08/21/2011] [Accepted: 09/14/2011] [Indexed: 12/25/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of β-sheet-rich amyloid oligomers or fibrils which are associated with cellular toxicity in the brain. Inhibition of Aβ aggregation could be a viable therapeutic strategy for slowing and/or preventing the progress of AD. Here we reported that α-mangostin (α-M), a polyphenolic xanthone derivative from mangosteen, concentration-dependently attenuated the neurotoxicity induced by Aβ-(1-40) or Aβ-(1-42) oligomers (EC(50) = 3.89 nM, 4.14 nM respectively) as observed by decreased cell viability and impaired neurite outgrowth in primary rat cerebral cortical neurons. Molecular docking and dynamics simulations demonstrated that α-M could potentially bind to Aβ and stabilize α-helical conformation. α-M was found to directly dissociate Aβ-(1-40) and Aβ-(1-42) oligomers by blotting with oligomer-specific antibodies. ThioflavinT fluorescence assay and electron microscopy imaging further demonstrated that α-M blocked the fibril formation as well as disturbed the pre-formed fibrils. Taken together, our results indicate that α-M is capable to inhibit and dissociate the Aβ aggregation, which could contribute to its effect of attenuating Aβ oligomers-induced neurotoxicity. Thus, α-M could be a great potential candidate for AD treatment. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
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Zheng R, Chen TS, Lu T. A comparative reverse docking strategy to identify potential antineoplastic targets of tea functional components and binding mode. Int J Mol Sci 2011; 12:5200-12. [PMID: 21954353 PMCID: PMC3179160 DOI: 10.3390/ijms12085200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Revised: 07/19/2011] [Accepted: 07/22/2011] [Indexed: 12/13/2022] Open
Abstract
The main functional components of green tea, such as epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG) and epicatechin (EC), are found to have a broad antineoplastic activity. The discovery of their targets plays an important role in revealing the antineoplastic mechanism. Therefore, to identify potential target proteins for tea polyphenols, we have taken a comparative virtual screening approach using two reverse docking systems, one based on Autodock software and the other on Tarfisdock. Two separate in silico workflows were implemented to derive a set of target proteins related to human diseases and ranked by the binding energy score. Several conventional clinically important proteins with anti-tumor effects are screened out from the PDTD protein database as the potential receptors by both procedures. To further analyze the validity of docking results, we study the binding mode of EGCG and the potential target protein Leukotriene A4 hydrolase in detail. We indicate that interactions mediated by electrostatic and hydrogen bond play a key role in ligand binding. EGCG binds to the enzyme with certain orientation and conformation that is suitable for nucleophilic attacks by several electrical residues inside the enzyme's activity cavity. This study provides useful information for studying the antitumor mechanism of tea's functional components. The comparative reverse docking strategy presented generates a tractable set of antineoplastic proteins for future experimental validation as drug targets against tumors.
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Affiliation(s)
- Rong Zheng
- Institute of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350108, China; E-Mail:
| | - Tuan-sheng Chen
- Institute of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; E-Mail:
| | - Tun Lu
- Institute of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350108, China; E-Mail:
- Fujian Supercomputer Center, Fuzhou, Fujian 350108, China
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12
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Ameen Abdulmajeed N. Therapeutic ability of some plant extracts on aflatoxin B1 induced renal and cardiac damage. ARAB J CHEM 2011. [DOI: 10.1016/j.arabjc.2010.06.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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Pohanka M, Sobotka J, Stetina R. Sulfur mustard induced oxidative stress and its alteration by epigallocatechin gallate. Toxicol Lett 2010; 201:105-9. [PMID: 21172412 DOI: 10.1016/j.toxlet.2010.12.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/05/2010] [Accepted: 12/13/2010] [Indexed: 12/20/2022]
Abstract
Sulfur mustard (bis(2-chloroethyl)sulfide; CAS: 505-60-2; abbreviated as HD) is a chemical warfare agent with not well understood mechanism of toxic effect. Deprivation of energy in cells and arising of oxidative stress appears during the exposure. Our experiment is based on investigation of 10mg or 20mg epigallocatechin gallate (EGCG) dose prophylactic effect (1h before HD) in rats exposed to either 20mg or 80 mg of HD. Blood mass, plasma and liver were sampled. Ferric reducing antioxidant power (FRAP), reduced glutathione, thiobarbuturic acid reactive substances (TBARSs), glutathione reductase, glutathione S-transferase and caspase 3 were assessed. Animals were sacrificed one day after exposure. We found significant deprivation of low molecular weight antioxidants due to EGCG but not due to HD. However, HD depleted reduced glutathione. EGCG has no effect to influence TBARS level. EGCG and HD up-regulated glutathione reductase and EGCG down regulated glutathione S-transferase in liver tissue. Regarding caspase, EGCG had anti apoptotic potency. We discuss potency to use EGCG to ameliorate redox balance after HD exposure. The data also appoints at difficulty in antioxidant therapy as prophylaxis to the oxidative stress related toxins exposure and ambivalent modulation of oxidative stress.
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Affiliation(s)
- Miroslav Pohanka
- Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 50001 Hradec Kralove, Czech Republic.
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M. Mohamed A, S. Metwall N. Antiaflatoxigenic Activities of Some Plant Aqueous Extracts Against Aflatoxin-B1 Induced Renal and Cardiac Damage. ACTA ACUST UNITED AC 2008. [DOI: 10.3923/jpt.2009.1.16] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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Ferrara N, Rinaldi B, Corbi G, Conti V, Stiuso P, Boccuti S, Rengo G, Rossi F, Filippelli A. Exercise Training Promotes SIRT1 Activity in Aged Rats. Rejuvenation Res 2008; 11:139-50. [PMID: 18069916 DOI: 10.1089/rej.2007.0576] [Citation(s) in RCA: 180] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Nicola Ferrara
- Department of Health Sciences, Faculty of Medicine, University of Molise, Campobasso, Italy
- S. Maugeri Foundation, Scientific Institute of Telese Terme, Telese Terme, Italy
| | - Barbara Rinaldi
- Department of Experimental Medicine and Excellence Center of Cardiovascular Disease, Second University of Naples, Naples, Italy
| | - Graziamaria Corbi
- Department of Health Sciences, Faculty of Medicine, University of Molise, Campobasso, Italy
- S. Maugeri Foundation, Scientific Institute of Telese Terme, Telese Terme, Italy
| | - Valeria Conti
- Department of Experimental Medicine and Excellence Center of Cardiovascular Disease, Second University of Naples, Naples, Italy
| | - Paola Stiuso
- Department of Biochemistry, Second University of Naples, Naples, Italy
| | - Silvia Boccuti
- Department of Experimental Medicine and Excellence Center of Cardiovascular Disease, Second University of Naples, Naples, Italy
| | - Giuseppe Rengo
- S. Maugeri Foundation, Scientific Institute of Telese Terme, Telese Terme, Italy
| | - Francesco Rossi
- Department of Experimental Medicine and Excellence Center of Cardiovascular Disease, Second University of Naples, Naples, Italy
| | - Amelia Filippelli
- Department of Experimental Medicine and Excellence Center of Cardiovascular Disease, Second University of Naples, Naples, Italy
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Hernandez MR, Miao H, Lukas T. Astrocytes in glaucomatous optic neuropathy. PROGRESS IN BRAIN RESEARCH 2008; 173:353-73. [DOI: 10.1016/s0079-6123(08)01125-4] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Tulayakul P, Dong KS, Li JY, Manabe N, Kumagai S. The effect of feeding piglets with the diet containing green tea extracts or coumarin on in vitro metabolism of aflatoxin B1 by their tissues. Toxicon 2007; 50:339-48. [PMID: 17537474 DOI: 10.1016/j.toxicon.2007.04.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Revised: 04/18/2007] [Accepted: 04/18/2007] [Indexed: 10/23/2022]
Abstract
To clarify whether enzymes involved in aflatoxin B1 (AFB1) metabolism in pigs respond to antioxidant agents, the effect of feeding piglets with diets containing green tea extracts (Sunphenon) and coumarin on in vitro AFB1 metabolism by their liver and intestinal tissues was studied. The results showed that coumarin reduced AFB1-DNA adduct formation by both liver and intestinal microsomes, while Sunphenon did not have any effects. Both coumarin and Sunphenon enhanced the glutathione S-transferase (GST) activity to conjugate AFB1 to glutathione GSH in the intestine, although no effects were noted in the liver. Changes of the expression of mRNA of GSTA2 and GSTO1 were not in parallel with the observed changes of GST activity, suggesting that other GST subtypes are involved in the GST activity toward AFB1. As for lipophilic-free AFB1 metabolites, coumarin reduced the liver microsomal conversion of AFB1 to aflatoxin M1 (AFM1) and aflatoxin Q1 (AFQ1), but Sunphenon exerted no effects. Both coumarin and Sunphenon enhanced the conversion of AFB1 to aflatoxicol in the liver. All the results suggest that feeding with a diet containing coumarin affects AFB1 metabolism to enhance AFB1 detoxification through the suppression of P450 enzyme activity in the liver and the enhancement of GST activity in the intestine. Feeding with a diet containing Sunphenon enhances AFB1 detoxification, but the effects are noted mainly in the intestine.
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Affiliation(s)
- P Tulayakul
- Graduate School of Agricultural and Life Sciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
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Wessner B, Strasser EM, Koitz N, Schmuckenschlager C, Unger-Manhart N, Roth E. Green tea polyphenol administration partly ameliorates chemotherapy-induced side effects in the small intestine of mice. J Nutr 2007; 137:634-40. [PMID: 17311952 DOI: 10.1093/jn/137.3.634] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The chemotherapeutic agent irinotecan (IT) is highly effective against several types of cancer, although its use is limited due to severe intestinal toxicity. The aim of this study was to evaluate inflammatory and oxidative stress-related processes contributing to small intestinal mucosa damage and to determine the extent to which green tea polyphenols could ameliorate the detrimental effects induced by IT. In Expt. 1, mice were challenged intraperitoneally with IT or saline on 2 consecutive days. For time kinetic measurements, the IT-treated mice were killed at 3, 24, 48, 72, and 96 h after the 2nd dose of IT. Three hours after IT administration, the ileum glutathione concentration dropped significantly. Lipid peroxidation and inflammation, as measured by macrophage inflammatory protein-2 content, myeloperoxidase activity, and nuclear factor-kappaB translocation, were highest between 24 and 48 h after IT treatment. In Expt. 2, green tea polyphenols (1 g/L) were supplied via drinking water for 7 d before and 3 d after treatment with IT. Green tea polyphenols significantly affected the glutathione:glutathione disulfide ratio but not lipid peroxidation, macrophage inflammatory protein-2 levels, myeloperoxidase activity, or nuclear factor-kappaB activation. Our study reveals that IT administration is associated with oxidative stress and inflammation, both occurring simultaneously to IT-induced mucosal damage. The antioxidative defense is affected soon after IT administration. Green tea polyphenols supplied orally protected against oxidation in our experimental model and could be one approach to reducing the risk of IT-induced side effects in the clinical setting.
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Affiliation(s)
- Barbara Wessner
- Department of Surgery, Research Laboratories, Medical University of Vienna, A-1090 Vienna, Austria.
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Malone PE, Hernandez MR. 4-Hydroxynonenal, a product of oxidative stress, leads to an antioxidant response in optic nerve head astrocytes. Exp Eye Res 2006; 84:444-54. [PMID: 17173895 PMCID: PMC1832079 DOI: 10.1016/j.exer.2006.10.020] [Citation(s) in RCA: 247] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2006] [Revised: 10/06/2006] [Accepted: 10/19/2006] [Indexed: 11/27/2022]
Abstract
Oxidative stress has been implicated in the pathogenesis of several neurodegenerative disorders including primary open-angle glaucoma (POAG) an optic neuropathy characterized by loss of retinal ganglion cell (RGC) axons and remodeling of the optic nerve head (ONH). Previous findings in glaucomatous astrocytes suggested increased oxidative stress and lipid peroxidation in human optic nerves. We studied the dose and time dependent effects of 4-hydroxynonenal (HNE), a by-product of lipid peroxidation, on the viability of primary cultures of human ONH astrocyte. A significant depletion of glutathione (GSH) level was observed in normal astrocytes after exposure to HNE for 1 h and 3 h. Untreated glaucomatous astrocytes exhibited depleted levels of GSH which increased slightly after exposure to HNE. Both normal and glaucomatous astrocytes recovered GSH levels after 24 h of removal of HNE. HNE caused significant increases in expression of antioxidant enzymes, glutamate cysteine ligase catalytic subunit (GCLC), aldo-keto reductase 1C family member 1 (AKR1C1) and glutathione S-transferase-alpha4 (GSTA4). HNE induced expression of the transcription factor Nrf2, which coordinates the upregulation of detoxification enzymes. In addition, ONH astrocytes responded to HNE by activation and transcription of cFOS and NFkB, which regulate physiological protective responses against oxidative stress. Our results indicate that ONH astrocytes exhibit a strong antioxidant response to HNE treatment by inducing the transcription factors cFOS, NFkB, and Nrf2, which upregulate the expression of GCLC, to produce more GSH in the cell. AKR1C1 was also upregulated after HNE treatment to inactivate HNE, independent of GSH availability in the cells. Collectively these data indicate that ONH astrocytes can efficiently counteract the neurotoxic effects of HNE offering protection in the optic nerve by releasing GSH and antioxidant enzymes to eliminate the products of chronic oxidative stress.
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Affiliation(s)
- P E Malone
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago, Tarry 13-711, Chicago, IL 60611, USA
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Raza H, John A. 4-hydroxynonenal induces mitochondrial oxidative stress, apoptosis and expression of glutathione S-transferase A4-4 and cytochrome P450 2E1 in PC12 cells. Toxicol Appl Pharmacol 2006; 216:309-18. [PMID: 16843508 DOI: 10.1016/j.taap.2006.06.001] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 06/01/2006] [Accepted: 06/02/2006] [Indexed: 11/18/2022]
Abstract
An excessive and sustained increase in reactive oxygen species (ROS) production and oxidative stress have been implicated in the pathogenesis of many diseases. In the present study, we have demonstrated that 4-hydroxynonenal (4-HNE), a product of lipid peroxidation, alters glutathione (GSH) pools and induces oxidative stress in PC12 cells in culture. This increase was accompanied by alterations in subcellular ROS and glutathione (GSH) metabolisms. The GSH homeostasis was affected as both mitochondrial and extramitochondrial GSH levels, GSH peroxidase and glutathione reductase activities were inhibited and glutathione S-transferase (GST) activity was increased after 4-HNE treatment. A concentration- and time-dependent increase in cytochrome P450 2E1 (CYP 2E1) activity in the mitochondria and postmitochondrial supernatant was also observed. 4-HNE-induced oxidative stress also caused an increase in the expression of GSTA4-4, CYP2E1 and Hsp70 proteins in the mitochondria. Increased oxidative stress in PC12 cells initiated apoptosis as indicated by the release of mitochondrial cytochrome c, activation of poly-(ADP-ribose) polymerase (PARP), DNA fragmentation and decreased expression of antiapoptotic Bcl-2 proteins. Mitochondrial respiratory and redox functions also appeared to be affected markedly by 4-HNE treatment. These results suggest that HNE-induced oxidative stress and apoptosis might be associated with altered mitochondrial functions and a compromised GSH metabolism and ROS clearance.
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Affiliation(s)
- Haider Raza
- Department of Biochemistry, Faculty of Medicine and Health Sciences, PO Box 17666, UAE University, Al Ain, United Arab Emirates.
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Raza H, John A. Green tea polyphenol epigallocatechin-3-gallate differentially modulates oxidative stress in PC12 cell compartments. Toxicol Appl Pharmacol 2005; 207:212-20. [PMID: 16129114 DOI: 10.1016/j.taap.2005.01.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Revised: 12/18/2004] [Accepted: 01/05/2005] [Indexed: 01/08/2023]
Abstract
Tea polyphenols have been reported to be potent antioxidants and beneficial in oxidative stress related diseases. Prooxidant effects of tea polyphenols have also been reported in cell culture systems. In the present study, we have studied oxidative stress in the subcellular compartments of PC12 cells after treatment with different concentrations of the green tea polyphenol, epigallocatechin-3-gallate (EGCG). We have demonstrated that EGCG has differentially affected the production of reactive oxygen species (ROS), glutathione (GSH) metabolism and cytochrome P450 2E1 activity in the different subcellular compartments in PC12 cells. Our results have shown that although the cell survival was not inhibited by EGCG, there was, however, an increased DNA breakdown and activation of apoptotic markers, caspase 3 and poly- (ADP-ribose) polymerase (PARP) at higher concentrations of EGCG treatment. Our results suggest that the differential effects of EGCG might be related to the alterations in oxidative stress, GSH pools and CYP2E1 activity in different cellular compartments. These results may have implications in determining the chemopreventive therapeutic use of tea polyphenols in vivo.
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Affiliation(s)
- Haider Raza
- Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.
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Abstract
BACKGROUND In this article, we review a diverse body of research and draw conclusions about the usefulness, or lack there-of, of specific antioxidants in the prevention of Alzheimer's disease (AD). METHODS The National Library of Medicine's database was searched for the years 1996-2004 using the search terms "Alzheimer's, anti-oxidants, antioxidants." RESULTS Over 300 articles were identified and 187 articles were selected for inclusion based on relevance to the topic. Agents that show promise in helping prevent AD include: 1) aged garlic extract, 2) curcumin, 3) melatonin, 4) resveratrol, 5) Ginkgo biloba extract, 6) green tea, 7) vitamin C and 8) vitamin E. CONCLUSIONS While the clinical value of antioxidants for the prevention of AD is often ambiguous, some can be recommended based upon: 1) epidemiological evidence, 2) known benefits for prevention of other maladies, and 3) benign nature of the substance. Long-term, prospective studies are recommended.
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Affiliation(s)
- Bradford Frank
- Department of Psychiatry, University of Buffalo School of Medicine and Biomedical Sciences, Buffalo, NY, USA.
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Neely MD, Boutte A, Milatovic D, Montine TJ. Mechanisms of 4-hydroxynonenal-induced neuronal microtubule dysfunction. Brain Res 2005; 1037:90-8. [PMID: 15777756 DOI: 10.1016/j.brainres.2004.12.027] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2004] [Revised: 12/13/2004] [Accepted: 12/17/2004] [Indexed: 11/24/2022]
Abstract
We have previously demonstrated that neuronal microtubules are exquisitely sensitive to the lipid peroxidation product 4-hydroxynonenal (HNE). The mechanism, however, by which HNE disrupts the microtubules, is not known. Sulfhydryl groups of protein-cysteines constitute main targets of HNE. Indeed, HNE is mainly detoxified by conjugation to glutathione (GSH), a reaction that leads to depletion of cellular GSH. GSH maintains protein sulfhydryl groups in the reduced form and has been implicated in the regulation of cytoskeletal function. Here, we assess what role depletion of cellular GSH plays in the HNE-induced microtubule disruption. We demonstrate that HNE and its intracellularly activated tri-ester analog, HNE(Ac)(3), cause substantial GSH depletion in Neuro2A cells. However, other compounds inducing GSH depletion had no effect on the microtubule network. Therefore, HNE-induced depletion of cellular GSH does not contribute to the HNE-induced microtubule disruption. We previously demonstrated that another main cellular target of HNE is tubulin, the core protein of microtubules containing abundant cysteines. The functional relevance of this adduction, however, had not been evaluated. Here, we demonstrate that exposure of Neuro 2A cells to HNE or HNE(Ac)(3) results in the inhibition of cytosolic taxol-induced tubulin polymerization. These and our previous observations strongly support the hypothesis that HNE-adduction to tubulin is the primary mechanism involved in the HNE-induced loss of the highly dynamic neuronal microtubule network.
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Affiliation(s)
- M Diana Neely
- Department of Psychiatry, Vanderbilt University Medical Center, 313 PHV, 1601 23rd Avenue South, Nashville, TN 37212, USA.
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Takuma K, Baba A, Matsuda T. Astrocyte apoptosis: implications for neuroprotection. Prog Neurobiol 2004; 72:111-27. [PMID: 15063528 DOI: 10.1016/j.pneurobio.2004.02.001] [Citation(s) in RCA: 350] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Accepted: 02/04/2004] [Indexed: 12/21/2022]
Abstract
Astrocytes, the most abundant glial cell types in the brain, provide metabolic and trophic support to neurons and modulate synaptic activity. Accordingly, impairment in these astrocyte functions can critically influence neuronal survival. Recent studies show that astrocyte apoptosis may contribute to pathogenesis of many acute and chronic neurodegenerative disorders, such as cerebral ischemia, Alzheimer's disease and Parkinson's disease. We found that incubation of cultured rat astrocytes in a Ca(2+)-containing medium after exposure to a Ca(2+)-free medium causes an increase in intracellular Ca(2+) concentration followed by apoptosis, and that NF-kappa B, reactive oxygen species, and enzymes such as calpain, xanthine oxidase, calcineurin and caspase-3 are involved in reperfusion-induced apoptosis. Furthermore, we demonstrated that heat shock protein, mitogen-activated protein/extracellular signal-regulated kinase, phosphatidylinositol-3 kinase and cyclic GMP phosphodiesterase are target molecules for anti-apoptotic drugs. This review summarizes (1) astrocytic functions in neuroprotection, (2) current evidence of astrocyte apoptosis in both in vitro and in vivo studies including its molecular pathways such as Ca(2+) overload, oxidative stress, NF-kappa B activation, mitochondrial dysfunction, endoplasmic reticulum stress, and protease activation, and (3) several drugs preventing astrocyte apoptosis. As a whole, this article provides new insights into the potential role of astrocytes as targets for neuroprotection. In addition, the advance in the knowledge of molecular mechanisms of astrocyte apoptosis may lead to the development of novel therapeutic strategies for neurodegenerative disorders.
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Affiliation(s)
- Kazuhiro Takuma
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences and High Technology Research Center, Kobe Gakuin University, Kobe 651-2180, Japan
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